Piano action



C. F. STEIN PIANO ACTION Nov. 7, 1950 2 Sheets-Sheet 1 Filed July 16, 1948 INVENTOR.

C. F. STEIN PIANO ACTION Nov. 7, 1950 2 Sheets-Sheet 2 Filed July 16, 1948 BY M Patented Nov. 7, 1950 UNITED STATES PATENT OFFICE 2,528,797 PIANO ACTION Charles Frederick Stein, La Grange, Ill., assignor to Pratt, Read and Company, Inc., Ivoryton, Conn., a corporation of Connecticut Application July 16, 1948, Serial No. 39,039

8 Claims.

This invention relates to piano actions and more particularly to an improved action for use with a piano having horizontal strings.

There has been a great demand in recent years for small pianos for use in small homes and apartments and also for use as practice pianos both in homes and in schools. To meet this need and at the same time provide a piano which is pleasing in appearance, a small horizontal piano has been developed. This piano is described in United States Patent No. 2,505,806 dated May 2, 1950, subject Piano. In such a piano the keys and action are both mounted above the strings so thatthe space is efiiciently utilized and a piano of very small size results. In this construction the piano hammers strike downwardly to engage the strings. In order to keep the size at a minimum and also provide an overall inexpensive structure, the piano action must be of simple and inexpensive as well as compact construction.

In order to provide free vibration of the strings and a true piano tone, th hammer must swing freely when it strikes the string and then move away from the string so that the string is struck only once. Also the hammer must return to an operative position very quickly so that the action will respond to rapid action .or repetition of the keys.

It is, therefore, an object of the present invention to provide an improved action for use in a piano having horizontal strings.

It is a further object of this invention to provid a simple action for a horizontal piano which provides rapid repetition, that is, repeated operation of the hammer by a piano key.

A feature of this invention is the provision of an action for a horizontal piano having a let-oif for releasing the jack so that the hammer swings freely to strike a string and then moves back from the string.

A further feature of this invention is the provision of a piano action in which the hammer includes a knuckle and an extending shoulder, with the knuckle being engaged by the jack to move the hammer, during normal operation and the shoulder being engaged by the jack when rapid repetition is required which does not permit the action to be restored to normal position between successive operations of a key.

Further objects, features and advantages will be apparent from a consideration of the following description taken in connection with the accompanying drawings in which:

Fig.1 illustrates a horizontal piano in which 2 the action in accordance with the invention may be used;

Fig. 2 is a detailed view of the piano action in accordance with the invention;

Fig. 3 illustrates th piano action in operated position; and

Fig. 4 illustrates a modified action structure.

In practicing the invention there is provided an action for a piano having horizontal strings which includes fixed rail structure, a hammer, and mechanism for applying movement of a piano key to the hammer. This operating mechanism includes a whip pivotally supported on the rail structure and having two ang ularly extending members one of which is adapted to engage the rear end of a piano key. The second member of th whip pivotally supports a jack which has an end in engagement with the butt of the hammer. The hammer butt includes a knuckle and a projecting portion extending therefrom. A spring is provided for biasing the jack to a position in which the end thereof engages the knuckle on the hammer butt. When the action is moved by a piano key, a hooked portion of the jack engages a let-ofi so that the end of the jack is moved away from the knuckle of the hammer butt. This allows the hammer to swing freely to strike a string and then return to a position away from the string. A back-check is secured to the second member of the whip to be engaged by the projection on the hammer butt to prevent bouncing of the hammer after it strikes a string. When the key is released, the mechanism returns to its normal position with the jack engaging the knuckle of the hammer butt. If, however, fast repetition of the hammer is required and the key is not completely raised to allow the action to return to the normal position, the end of the jack engages the shoulder on the hammer butt to cause the hammer to be moved by the key to provide rapid action of the hammer.

Referring now to the drawings, in Fig. 1 there is illustrated a horizontal piano including a case It! supported by legsi l. A frame 52 is provided inthe case and supports the operating structure including the piano keys, strings, action and a sounding board. The frame I 2 extends under the piano keys l3 and the action l4 so that the entire horizontal area of the piano is utilized by the strings. A lyre structure l5 may be provided including pedals operatively connected to the piano action for effecting the operation thereof. The relations of the keys and actions to the frame, strings and sound board are shown in Fig. 2 in 3 which the strings are indicated at It, the sounding board H and the pinblock l8.

Referring now more particularly to the piano action, in Figs. 2 and 3 the action is illustrated as including rail members I9, 20, 2! and 22 which may be supported by brackets in the usual Way. Pivotally mounted on the rail 26 are the hammer 23 and the whip 24. The hammer includes a head 25 and a butt 26 with the head being normally positioned above the string and adapted to strike the string as the hammer is rotated in a counter-clockwise direction. The hammer butt includes a knuckle 21 and an extending shoulder 28 both of which are preferably covered by felt or similar resilient material. The fixed rail 2| supports a spring 80 which holds the hammer in the normal position away from the strings. Resilient material such as felt as indicated at 4| is secured to the rail 2! and serves as a stop to limit movement of the hammer 23.

The whip 2% is formed by two members indicated at 29 and 30 which extend at an angle with respect to each other. The pivotal mounting for the Whip is adjacent the intersection of the two members. A capstan screw 3! is threaded in the member 29 and engages the end 32 of key N! to thereby provide an operative connection between the key It and the action M. In order to transmit this movement of the key I3 to the hammer 23, a jack 33 is pivotally supported on the member 30 of the whip and is biased by the spring 35 so that the end 35 thereof normally engages the knuckle 2'! of the hammer butt. A let-off 36 is secured to the rail 22 and positioned to be engaged by the hook portion 31 of the jack as will be further described. To prevent undesired movement of the hammer, a back-check 38 is secured to the member 39 of the whip and is adapted to engage the end 39 of the hammer butt 26.

A damper 45 is also pivotally supported on the rail 2!! and is normallyheld against the string it by spring 45. A spoon M is secured to the whip 2d and is adapted to engage extension 48 on the damper for raising the damper from the string when the action is operated. A damper release 59 is also provided which may be operated through rod 59 connected to the pedal mechanism so that the damper can be released by the pedals in the usual way.

Considering now the operation of the action, reference is made to Fig. 3 which shows the action in operated, position. The key. 53 is depressed and the whip 24 is rotated thereby in a counter-clockwise direction. The movement of thewhip is transmitted through jack 33 to the hammer 23 to cause counter-clockwise rotation of the hammer. The hook 3'! of the jack 33 engages the let-off 36 and this causes the jack to be rotated in a clockwise direction so that the end 35 thereon is released from the knuckle 21 of the hammer butt. In the position shown the key is fully depressed and although the hammer is not in engagement with the string it, the momentum of the hammer will cause it to continue until the head 25 strikes the string It. The hammer will then move back due to action of spring 40 to the position shown in Fig. 3, in which the back-check 38 engages the end 39 of the hammer butt 26 to prevent further movement.

It will be noted that in the operated position of the action, the end 35 of the jack 33 is in engagement with the shoulder. 28 on the hammer butt. This provides an operative connection between the key and the hammer even after the hammer has struck a, string and while the key is still depressed. Therefore, if it is desired to repeat a note very rapidly so that the key is not completely raised to allow the action to be completely restored to the normal position as shown in Fig. 2, the engagement of the end 35 of the jack and the shoulder 28 of the hammer butt will transmit movement of the key to the hammer so that rapid repetition is provided.

In Fig. 4 there is shown a slightly modified action in which the rail I9 is of difierent construction and the spring 40 for holding the hammer in the proper position is supported from this rail. The specific shape of the hammer butt is slightly changed to provide the required cooperation of the spring 40 but the cooperation between the jack and the knuckle and shoulder of the hammer butt is exactly as previously described. The action is otherwise identical and will operate in exactly the same manner as the action illustrated in Figs. 2 and 3.

The piano action described above provides all the desired features in a construction which is simple and compact and is, therefore, suitable for a small piano having horizontal strings. The

hammer swings freely when it strikes the string so that a pure piano tone is produced. The hammer is then checked to prevent undesired bouncing action. The cooperation between the jack and the hammer butt produces this free movement of the hammer and also provides an operative connection between the key and hammer at all times so that rapid repetition is possible.

While I have described certain embodiments of my invention which are illustrative thereof, it is obvious that various changes and modifications can be made therein without departing from the intended scope of the invention as defined in the appended claims.

I claim:

1. An action for a piano having horizontal strings including in combination fixed rail means, a hammer including a butt pivotally mounted on said rail means, said butt including a knuckle and a projecting shoulder portion, a spring secured to said rail means for normally holding said hammer away from said strings, a whip including a pair of angularly disposed members pivotally mounted adjacent the intersection of said members on said rail means, one of said members of said whip engaging a piano key to be actuated thereby, a jack pivotally secured to the other one of said members and including an end engaging the butt of said hammer, a spring tending to hold said jack in a position so that said end engages said knuckle on said hammer butt, and let-ofi means positioned to be engaged by said jack When said piano key is operated to move said end of said jack away from said knuckle to a position in engagement with said shoulder portion of said hammer butt.

2. An action for a piano having horizontal strings including in combination fixed rail means, a hammer including a butt pivotally mounted on said rail means, said butt including a knuckle and a projecting shoulder portion, spring means secured to said rail means for normally holding said hammer away from said strings, a Whip including a pair of angularly extending members pivotally mounted adjacent the intersection of said members on said rail means, one of said members of said whip engaging a piano key to be actuated thereby, a jack pivotally secured to the other one of said members and having one end which engages the butt of said hammer and a second hook shaped end, a spring tending to hold said jack in a position so that said one end engages said knuckle on said hammer butt, and let-off means positioned to be engaged by said hook shaped end of said jack when said piano key is operated to move said one end of said jack away from said knuckle to a position in engagement with said shoulder portion of said hammer butt.

3. An action for a piano having horizontal strings including in combination fixed rail means, a hammer including a butt pivotally mounted on said rail means, said butt including a knuckle and a projecting shoulder portion, spring means secured to said rail means for normally holding said hammer away from said strings, a whip pivotally mounted on said rail means, said whip including a portion engaging a piano key to be actuated thereby, a jack pivotally secured to said whip including an end engaging the butt of said hammer, spring means tending to hold said jack in a position so that said end engages said knuckle on said hammer butt, and let-off means positioned to be engaged by said jack when said piano key is operated to move said end of said jack away from said knuckle to a position in engagement with said shoulder portion of said hammer butt.

4. An action for a piano having horizontal strings comprising, a hammer pivotally mounted in a position to strike a string, said hammer including a butt having a knuckle and a vertically extending shoulder thereon, a whip, a jack pivotally mounted on said whip and extending substantially horizontally with one end thereof engaging said hammer butt, means for holding said jack so that said one end thereof engages said knuckle, and means effective to release said one end of said jack from said knuckle when said whip is operated, said one end of said jack being adapted when released to contact said shoulder of said hammer butt so that rapid repeated movement of said whip causes said hammer to repeatedly strike said string.

5. An action for a piano having horizontal strings comprising, a hammer pivotally mounted in a position to strike a string, said hammer including a butt having a knuckle and a vertically extending shoulder thereon, a whip, a jack pivotally mounted on said whip having one end which engages said hammer butt and a second hook shaped end, spring means for holding said jack so that said one end thereof engages said knuckle, and a let-ofi positioned to be engaged by r said hook shaped end for releasing said one end of said jack from said knuckle when said whi-p is operated, said one end of said jack being adapted when released to contact said shoulder of said hammer butt so that rapid repeated movement of said whip before said action is restored causes said hammer to repeatedly strike said string.

6. An action for a piano having horizontal .shoulder thereon, a whip,

strings comprising a hammer pivotally mounted in position to strike a string, said hammer including a butt having a knuckle and a vertically extending shoulder thereon, a jack extending substantially horizontally and having one end which engages said hammer butt and a second hook shaped end, spring means for holding said jack so that said one end thereof engages said knuckle, and a let-off positioned to be engaged by said hook shaped end for releasing said one end of said jack from said knuckle when said whip is operated, said one end of said jack being adapted when released to contact said shoulder of said hammer butt so that said jack and said hammer butt are in contact at all times for rapid repetition.

7. An action for a piano having horizontal strings including in combination fixed rail means, a hammer including a butt pivotally mounted on said rail means, said butt having a knuckle thereon, spring means secured to said rail means for normally holding said hammer away from said strings, a whip including a pair of angularly extending members pivotally mounted adjacent the intersection of said members on said rail means, one of said members of said whip engaging a piano key to be actuated thereby, a horizontally extending jack pivotally secured to the other one of said members and having one end which engages the butt of said hammer and a second hook shaped end, a spring tending to hold said jack in a position so that said one end engages said knuckle on said hammer butt, and let-01f means positioned to be engaged by said hook shaped end of said jack when said piano key is operated to move said one end of said jack away from said knuckle.

8. An action for a piano having horizontal strings comprising, a hammer pivotally mounted in a position to strike a string, said hammer including a butt having a knuckle and a projecting a jack pivotally mounted on said whip having one end which engages said hammer butt, spring means for holding said jack so that said one end thereof engages said knuckle, and a let-off positioned to be engaged by said jack for releasing said one end of said jack from said knuckle when said whip is operated, said one end of said jack being adapted when released to contact said shoulder of said hammer butt so that rapid repeated movement of said whip before said action is restored is transferred through said jack to said shoulder and causes said hammer to repeatedly strike said string,

CHARLES FREDERICK STEIN.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 956,003 Vincent Apr. 26, 1910 

